Winding mandrel



Apr. 3, 1923.

Filed July 51, 1920 PATENT QFFICE.

OMER E. COTE, OF PAWTUGKET, RHODE ISLAND.

WINDING MANDREL.

Application filed July 31,

To all whom it may concern: 7

Be it known that I, OMER E. Corn, a citizen of the United States, residing at Pawtucket, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Winding Mandrels, of which the following is a specification.

This invention relates to the construction of a core, mandrel or arbor on which material such as wire, thread, yarn lacings, tapes or other similar strands or strips of material may be wound with the so-called diagonal or V-sha'ped wind, and this invention has for its object to provide means in such a core or mandrel for engaging the knuckles or return-bend portions of the material and prevent them from slipping laterally inward on. the winding surface from the edge thereof, which slipping effect disarranges, the spacing. of the. wind at the edges of the package which in the case of electrical coils reduces the efliciency thereof rendering the coil defective.

The nature and advantages of the invention will be better understood when the following detail description is taken in connection with the accompanying drawings, the invention residing in the combination and arrangement of parts as claimed.

In the drawings forming part of this specification, like numerals of reference indicate similar wherein p- Figure 1 is a face view of my improved winding mandrel, showing strands of wire wound thereon with the knuckle portions parts in the several views and or return-bends ofthe wire as engaging the shoulder portions from sliding inward laterally on the winding surface of the man. drel.

Figure 2 is a perspective view showing one form of my improved mandrel.

Figure 3 is a sectional edge elevation illustratin shoulders formed on the opposite edges of the'*=winding surface of the mandrel for the purpose of receiving and retaining the knuckle portions or bends of the material wound thereon.

Figure 4 is a modified form illustrating a groove formed in the face of the mandrel into which the knuckle portions or bends of the wire are set at the edges of a diagonal wind.

In the construction of electrical inductance coils it is found in practice particu 1920. Serial N0. 400,372.

larly where the wire is wound by what is known as-the diagonal or V-wind upon the ordinary smooth-faced mandrel, that the wire at the knuckles or return-bend will slip or slide laterally inward on the winding surface of the mandrel towards the middle portion thereof, which slipping or sliding eifect breaks'up the symmetry of the wind and reduces the efficiency and .value of the coil,

The following is a detail description of an improved mandrel by which the above difficulties are obviated With reference to the drawings, 10 designates my improved mandrel which may be constructed in any suitable form either tubular or solid and of any suitable length and of any suitable material. Tn some cases especially when these mandrels are to be used in the forming of electrical inductance coils, I sometimes make them of paper tubes with shoulders 11 formed at either end of the tubing. Que simple construction of such a tubing is to form two superimposed tubular layers, the outer layer 12 being of less width than that of the inner layer 13 and the two layers may be cemented or otherwise connected together thus forming shoulders 11 at the ends of the winding surface 15 thereof, but I do not wish to be restricted to this particular construction whereby these shoulder portions are formed as the mandrel may be made of wood, fiber, metal, or other suitable material and the shoulders formed by drawing, swaging, turning, or by any other suitable method.

In some cases instead of forming shoulders at the extreme opposite ends of the mandrel I may form grooves 14 in the face "of the mandrel, as illustrated in Figure 4:, and in some cases two or more layers of the wire or material wound thereon may lie side by side in 1 these grooves, recesses or depressions which may be caused by the different spacings er the windings.

Upon laying the diagonal or V-windupon the surface of my improved mandrel, as the same reaches the edge of the windihg surface it is'naturally drawn down over the shoulder 11 at the edge thereof, the knuckle portions 16 being laid along for a short distance over this edge after which thematerial is caused to ride back over the edge 17 of the slipping or slidinginwardly upon .this surface .thereby insuring the windin'gof mechanically perfect coils which was not possible in a practical way on a mandrel without some means of holding or looking these return-bends against such lateral displace; ment. l

The foregoing description is directed solely towards the construction illustrated,

but I'desire it to be understood that I reserve the privilege of resorting to all the mechanical changes to whichthe device is susceptible, the invention being defined and limited only bythe terms of the appended claims. I claim: 2 1. A wire winding mandrel having sharpang-le continuous unobstructed shoulders over 'whichthe knuckle portions of material are wound diagonally thereon and retained thereby. V

2. A wire winding mandrel having recessed portions in its surface at the edge of its winding surface providing sharp-angled unobstructed shoulders for engaging the knuckle portions of the material'wound diagonally thereon.

3. A wire winding mandrel having an annular sharp-angled annular continuous unobstructed edge shoulder portion over which the knuckle portions of a wireor strand is laid when wound diagonally thereon to prevent the strand from slipping laterally on said winding surface.

4. A winding mandrel formed of two superimposed layers of tubing the outer layer being of a width less than that of the inner layer providing sharp-angled unobstructed annular. shoulders at the opposite edges of its winding surface.

In testimony whereof I aifix my signature.

- OMER E. COTE. 

